The prior art reveals a plethora of small light emitting devices to be worn by a user not only for the purposes of illumination but also for notification, alerting and identification. Recent improvements in high-intensity light emitting diodes (LEDs) have allowed arrays of small high-intensity lights of differing colours or wavelengths to be combined in a single signalling device. By equipping these prior art devices with a suitable microprocessor or microcontroller, a series of signalling programs and a multi-position switch for program selection, the array of LEDs can be turned on and off and their intensity varied according to the selected program.
There also exist in the art portable signalling devices comprising an array of user selectable LEDs, with at least one diode emitting light in the visible light range and at least one emitting light in the infra-red range. As is known in the art, devices operating in the infra-red range are not visible to the naked eye, but are typically visible for many miles to an observer equipped with, for example, a night vision system including a suitable infra-red image intensifier. In these prior art devices, the user typically selects the light to be emitted via a switch mechanism, with one favoured prior art switch being the bezel mounted multi-position rotary dial for rotation in a clockwise or counterclockwise direction.
One drawback of these prior art signalling devices is that the number of programs which can be selected is typically limited by the number of positions available on the multi-position switch. Another drawback is that such prior art devices do not present a means to reprogram the signalling programs if this is so desired. Still, another drawback with such prior art devices is that it is fairly simple for the user to err in his selection of the visible light and infrared light. In a night time situation, the selection of visible light when infra-red light is intended can have a number of dire consequences, including temporarily affecting the user's night vision or exposure of the user's position which, in a battle situation, can lead to serious injury or even death.